1. Field of the Invention
This invention relates to a closed, but vented, receptacle contructed of good heat transfer material and partially filled (approximately 1/3) with a eutectic solution. The upper portion of the interior of the receptacle includes CO.sub.2 spray head structure for forming CO.sub.2 snow therein, which snow may fall down upon the surface of the eutectic solution, and the lower portion of the interior of the receptacle includes structure for creating a predetermined path of circulation of eutectic solution within the approximate 1/3 lower portion of the receptacle, which circulation of eutectic solution is accomplished by jet discharging liquid CO.sub.2 into the inlet end portion of a circulation pipe including a horizontal leg disposed in the bottom of the receptacle and opening outwardly of one side wall of the receptacle adjacent the bottom thereof, a vertical leg extending upwardly from the end of the horizontal leg opening outwardly of the receptacle side wall and an upper L-shaped leg extending inwardly through an upper portion of a side wall of the tank above the level of eutectic solution therein and terminating inwardly in a down turned outlet end portion, the down turned outlet end portion being disposed above the surface of the eutectic solution in an area thereof remote from the inlet end portion of the first mentioned horizontal leg of the circulation pipe. All portions of the circulation pipe disposed exteriorly of the receptacle being covered by a suitable insulating covering.
2. Description of Related Art
My prior U.S. Pat. No. 4,848,095, dated July 18, 1989 discloses all of the instant invention, except for the circulation pipe of the instant invention.